[52.02] Lunar Na during the 1997 Leonid meteor shower

D.M. Hunten, A.L. Sprague (LPL, U. Arizona), G. Cremonese (U. Padua)

We describe attempts to observe an enhancement in the Na
atmosphere of the Moon during the 1997 Leonid shower,
November 16 -- 18. We also report observations of the
meteors by members of the Association of Lunar and Planetary
Observers and the North American Meteor Network. These
results show a peak, a few hours wide, at about 12:50 UT on
November 17; we also saw a number of bright meteors, perhaps
one every few minutes. We find an enhancement of lunar Na of
about 17 percent, but it is not statistically significant.
It also appears to last the entire 3 days of our
observations, so if it is real it must be related to a cloud
of much smaller meteoroids than those of the main peak, with
a considerably longer duration. Prospects are not good for
lunar observations in 1998, because the event occurs close
to New Moon; 1999 is much more favorable, just before third
quarter.